Original Articles: 2015 Vol: 7 Issue: 2
Preliminary phytochemical and antimicrobial evaluations of the methanolic leaf extract of Ochna kibbiensis Hutz and Dalz (Ochnaceae)
Abstract
The antimicrobial effect of the crude methanol leaf extract of Ochna kibbiensis obtained through maceration technique was evaluated against pathogenic microorganisms which include Staphylococcus aureus, Methicillin Resistant Staphylococcus aureus (MRSA), Vancomycin Resistant Enterococci, Listeria monocytogenes, Helicobacter pylori, Campylobacter fetus, Proteus vulgaris, Pseudomonas flourescens, Candida tropicalis and Candida stellatoidea. Agar Disc diffusion and Nutrient Broth dilution techniques were employed. Susceptibility test results showed that the extract (400μg) inhibited the growth of all the test organisms (bacteria and fungi) with a mean zone of inhibition range of 18-27mm, with the exception of Methicillin Resistant Staphylococcus aureus, Helicobacter pylori and Pseudomonas flourescens. The standard antibacterial drug, Sparfloxacin (5ug/ml) had inhibitory activity against all the organisms except H. pylori, P. flourescens, C. tropicalis and C. stellatoidea while Fluconazole, the standard anti-fungal drug showed activity only on the two fungi species tested C. tropicalis and C. stellatoidea. The Minimum Inhibitory Concentration (MIC) and the Minimum Bactericidal/Fungicidal Concentration (MBC) range for the extract was 5-20mg/ml and 10-40mg/ml, respectively. Preliminary phytochemical screening revealed the presence of flavonoids, steroids/terpenes, saponins, glycosides and alkaloids in the extract. The results of this study suggest that the leaves extract of the plant O. kibbiensis contains bioactive constituent(s) with good antibacterial and antifungal activity and, lends credence to its folkloric use in wound healing and other microbial infections.